I noticed that a lot of trivial tags (like yeti and blank) are becoming character tags recently

There's nothing wrong with that per se, but it does cause some confusion further down, when another character with an identical name pops up, and as the post count increases for them, it becomes harder and harder to find the specific character you're looking for.

So, how do you work around this? The answer to that, is making use of qualifiers
What's a qualifier? It's something (usually a single word) appended onto the end of a tag in brackets to make it unique from another identical tag. Similar, but different to the *_(artist) and *_(character) tags.

For example: There's the character Peri, who seems to be both a slender white-furred female cat (post #159871), and a muscled blue-scaled alligator (post #170324).

If you did a search for peri, assuming you didn't know what species they were, how do you find the one you're looking for?

• The easiest (and sometimes best) solution would be appending the name of the person to whom the character is credited to, be it the artist, or someone else

In this case, Peri the cat would become peri_(peridotkitty), and Peri the alligator would become peri_(mudwolfy)

• Another possible method would be using the series/franchise name, in the case of popular characters

e.g raven_(teen_titans), duke_(bad_dragon), or felicia_(darkstalkers)

It's a bit more typing at first, but it's more than worth it when you take into account all the possible characters and artist there are on e621